1. Field of the Invention
The invention relates to a drive device mounted in a vehicle body which includes a variable compression ratio internal combustion engine capable of changing the compression ratio.
2. Description of the Related Art
In the related art, there has been proposed a piston reciprocating type variable compression ratio internal combustion engine that changes the compression ratio by moving a cylinder block relative to a crankcase in the direction of an axis of a cylinder (hereinafter, referred to simply as “the up-down direction”) (see, e.g., Japanese Patent Application Publication No. 2003-206771 (JP-A-2003-206771)).
Incidentally, a piston reciprocating type internal combustion engine has a chain mechanism for rotating a crankshaft and camshafts in a coordinated manner, and a chain case that covers the chain mechanism. The chain mechanism is provided on a front surface of an engine body (including the crankcase and the cylinder block) (i.e., a surface of the engine body opposite from a surface thereof to which a transmission device is coupled). The chain case is fixed to the engine body by bolts.
On the other hand, a drive device of a vehicle which includes an internal combustion engine and a transmission device is supported on a vehicle body at least two sites. For example, one of the two sites is the chain case that constitutes a front surface of the engine body, and the other site is the transmission device.
The chain case of the aforementioned variable compression ratio internal combustion engine is divided into a cylinder block-side chain case fixed to the cylinder block and a crankcase-side chain case fixed to the crankcase since the cylinder block and the crankcase are moved relative to each other. However, it has not been thoroughly considered how a drive device that includes a variable compression ratio internal combustion engine provided with divided chain cases and a transmission device is to be supported on a vehicle body.